Fuel-feeding mechanism for underfeed stokers



BEST AVAILABLE COP\ Nov. 2, 1926.

J. A. FLEMINGS FUEL FEEDING MECHANISM FOR UNDERFEED STOKERS Filed April 26. 1925 war-3 12.529

Patented Nov. 2, 1926.

"UNITED STATES:

BEST AVAILABLE COP:

PAT ENT 'ironn A; FLnmrNes, or SHARON, MASSACHUSETTS. Assrenoa TO B; r. sruarnvanr I coMrANY; or HYDE PARK, mssacnusnrrs, A "coaroaa'rron or MASSACHUSETTS.

' I FUEL-FEEDING MECHANISM FOR 'UNDERF EED S'JlOKIErR/i.

Application filed April 26,1928. Serial No. 634,801..

The invention relates to means for feeding fueltounderfeed stokers.

Stokers of thischa-racter are usually provided with one or more retorts, into the front end of which the" fuel is forced by .a feeding plunger, and. from the open top of which the fuel) spreads-..-laterally -'onto the fuel supportingsurfacesor .grates. at the side .or sides of the retort. Thefuel fed in by theplunger may be moved along the bottom of the retort, to secure the proper distribution to the fuelbed, by a series of pushers .secured to a reciprocating pusher bar which is usually located within and close to the bottom of the retort.

One object of the present invention is to provide a. construction and arrangement of pushers which will avoid the buckling or springing upward of the .bar and the attached pushers under the resistance offered by the fuel to the advance of the pushers, or .by reason. of the packing of the fuel between the bottom of the retort and the bar or pushers. This isaccomplished by providing the pusher blocks with ribs which project laterally into longitudinal guiding.

grooves formed in the side walls of the retort and preferably at the base of each wall. With this construction the pushers slide along the bottom of .the retort :and are maintained in fixed relation thereto by the ribs and grooves so that vertical movement of the pushers within the retort .is prevented.

A further .object of the invention is to pro- .vide- -for the adjustment of the-pushers on the pusher rod to vary their distributing effect on the. fuel without disturbing the fuel bed or requiring theremoval of the. fuel from the retort. This is accomplished by .ofthe othe and a-construction embodying guiding. grooves 22 formed .at the bases of theside walls 24-ofthe retort. Bythis v conmounting the pusher bar in a slot passing stoker to vary the distribution without removmgor disturbing the fuel bed. The adjustments may therefore, be made under operating. conditions and .the desired distributron ,be secured and maintained without .in-

convenienceand loss of time,

- E e ea u eontli ed. abb em y b lized-in combination" with or; independently both feature's; is shown in the drawings. Fig. 1. is aqvertical;.sectionaltiew through the center oftthe fuelretort of an. underfeed stoker, Fig. 2 is a transversesectionalview on a larger scale taken on the line 2 2, Fig. 1, and Fig. .3' is a sectionaldetail on :line 3-3,Fig.2. j In the construction shown fuel isfed into the forward end of theretortfQby the feeding plunger 4. which .is; reciprocated by the crank .6-and connecting rod8and forcesthe fuel from the'hopper .l 0throughgthe feed throat 12 inthe usualmanner... 1' The 'fuel is movedalong in the retort by a series of pushers 14:.which cooperates with the plunger in forcingthe fuel up between the tuyere blocks-16 so that it spreads over .the upper surfaces of theiblocks and of the usual grate surfaces arranged at the Sides of the retort. The pushers are in the form j of blocks ,arrangedt slide along the :stationary bottom 18-01? the retort and retained and guided by ribsQO which project from the sides ofthe blocks pinto longitudinal struction the pushers are positively and-uniformly guided and their vertical relation to the bottom of the retort and to the fuel therein ismaintained with aresulting uniform action on the fuel.

The pusher blocks are reciprocated. by a rectangular pusher bar 26 which vfits within and fills a slot 28 in the bottomof the re tort. The slot extends through the bottom of the retort and the bar is supported in the slot by a series of short cover plates 30 which under lie the bar and are boltedto flanges 32 on the under side of the retort bottom. By removal of one or more of the cover plates access may be had to the bar from below the retort at any desired point or points for BEST AVAILABLE COPY the purpose of adjusting one or more of the 2. An underfeed stoker having, in combipushers on the bar. To enable this adjustnation, a horizontal fuel retort, each side ment to be conveniently made while the wall of which is provided at its base with a fuel remainsihf the retort'each pusher is conlongitudinal groove, pushers spaced along nected "with'tlre barby two pins 34; which the bottom of the retort'and arranged to may be inserted in any pair of two series move back and forth relatively thereto and ofholes 36 formed in the bar. lhe lower 4 adapted tofeed fuel upwardly through sutheir readjusted positions.

ends of theholes are countersunktorecmve ,perposed horizontaltuyeref ,blocks', ribs on the heads of the pins which are retained in the holes by the-cover iplates. The-uppers ends of the pins project above the upper surface of the bar and engagethe opposite ends of v the corresponding pusher blocks. \Vhen a piisherblo'clris tobe adjusted-the cover plates'which normally underlie tlie'two series of holes 36' correspondin' to the'pushe'r to be adjusted are iemoved to'give access to the pins 34. One of the pins'is 'then shifted into the hole corresponding to the desired position'of' the pusher, the bar 2'6 is then' moved to bring this pininto engagement with the end of "the pusher, which movement will uncover the other pin hole 36 of the pai'r corresponding *to this'positio'n of the pusher so t'hat'the other 'pin'may be inserted in the bar. The cover plates are then replaced so that the pins are retained in The relative positions of the pushers on the bari'n'ay thus be quickly and conveniently shifted to vary the distribution of the fuelin the'fuelbed without disturbing the fuel or requiring any material interruption in the operation of the feeding mechanism. The adjustments may be made under operating conditions and consequently the most efiicient distribution may be secured and maintained.

The bar 26 is reciprocated from the feed ing plunger by a lug 38 secured to the under side of the plunger and arranged to'engage or play between lugs'40 which are 'adjustably secured to the bar to vary the lost motion between the plunger and-bar and thus the movement'given to the bar by the reciprocation of the plunger.

While itis preferred to employ the specific construction and arrangement of parts shown and described it will befu'nderstood that this construction and arrangement is not essential to the broader features of the invention and may be varied or modified as found desirable or best suited to the construction and mode of operation of the stoker in which it'is to be embodied.

What is claimed is:

' 1. An underfeed stoker having, in combination, a horizontal fuel retort provided with longitudinal guiding grooves, pushers spaced along the bottom of the retort and ar ranged to move back and forth relatively thereto, and adapted'to feed fuel upwardly through superposed horizontal tuyere blocks,:

ribs on the pushers projecting into the grooves,"a11d a'push bar connected to the pushers for reciprocating the latter.

the pushers projecting laterally into the grooves aanda a. push bar. connected with the pushers for reciprocating the latter.

An underfeed' stoker having, in combination, a fuel retort provided with a longitudinal slot extending-through 'ite'bottom, a push bar in the slot, pushers in'the-ret'ort, and devices accessible from the under side of the retort for adji'ilstably connecting the pushers with said push bar. I g

{4. An underfeed stoker having, in-combination, a fuel retort provided with a longi- 'tudinal slot-extending through itsibottom, a

rectangular push bar filling the slot, pushers in the retort overlying the bar,-devices accessible from the under side of the retort .for adjustab'ly connecting the pushers with the bar, and a series of removable cover plates underlying the bar.

5. An underfeedstoker having, in combination, a fuel retort having a longitudinal slot extending through its bottom and a longitudinal-groove along the base tr each side Wall, a push-bar in the slot,- pushers in the retort provided with ribs extending laterally into the grooves,and devices accessible'from the under side of the retort for adjustably connecting the pushers with the bar.

6. An underfe'ed stoker having, in combination, a fuel retort havin'g'a longitudinal slot extending through its bottom'and a longitudinal groove along the base"of each side W-all,:a push bar in the slot, 'pushers in the retort provided with ribs-extending laterally into the grooves, two'series-ofholes in the bar corresponding to each pusher, two pins for each pusher, each pin passing through one of a pair of holes in the two series and engaging'opposite ends of the corresponding pusher and a series of removable cover plates underlying the bar.

7. An 'underfeed stoker having, in combination, a fuel retort having a longitudinal slot extending through its bottom,-a push bar in the slot, pushers in the retort, two series of holes in thebar corresponding to each pusher,'and two pins for each pusher. each pin passing through one of a pair of holes in the two series and engaging opposite ends of the corresponding pusher.

8. An'underfeed stoker having, in combination, a fueL retort provided with oppositely disposed longitudinal guiding grooves, a plurality of spaced separated pushers aligned'in the bottom of the retort and havl-ng-ribs projecting-laterally into the grooves, and a push bar extending beneath the pushers and independently connected with each pusher for reciprocating the same.

9. An underfeed stoker having, in combination, a fuel retort provided with a pair of longitudinally disposed grooves extending throughout the length of the retort, a plurality of independent separated pushers aligned in the retort and having ribs engaging with said grooves, a push bar for reciprocating the pushers, and means for independently connecting each pusher to the bar having provision for varying the position of the pusher longitudinally of the retort.

- JOHN A. FLEMINGS. 

